In the ice biome is a 2 block wide hole past the mechanic and goblin tinkerers houses. It will lead to the farm. You have to place something like a water bottle on your A key, and use the conveyor inside the safe room as a treadmill for the chaos elementals to spawn. The switch toggles the farm to burn money or to keep money. If you want the rod then keep it on burn the money. If the torch beside the switch is off, that means it's on burn money mode. The timer is to activate traps. You might want to bring a campfire and heart lanterns for protection against hallowed mimics, but putting a summon such as a raven in the spiky ball pit directly under the safe room will prevent the mimics from dashing upwards. If the biome at the farm is an ice biome for some reason, then remove a bit of the pink ice. It's recommended to use tanky accessories like frozen shield, celestial shell, ect.
